Some surgical interventions involve piercing or cutting a hole into a tissue wall. For example, thoracoscopic procedures typically involve piercing one or more tissue walls with a trocar or other sharp device and insertion of a cannula to maintain an opening in the tissue. Surgical instruments may be inserted through the cannula in order to access a surgical site disposed beyond the tissue. For example, a thoracoscopic cardiac procedure may involve a trans-apical valve repair. This procedure requires access to the outer wall of patient's heart, e.g., via a small intercostal hole in the patient. This procedure further involves piercing the outer wall of the heart to form an access hole, and insertion of a cannula to maintain a desired diameter of the access hole and to protect the pierced heart tissue during subsequent insertion and/or removal of thoracoscopic tools through the cannula. Thoracoscopic surgical tools may then be inserted through the cannula and into one or more chambers of the heart in order to repair defects or damaged portions of the heart.
Further, some pericardiocentesis procedures involve inserting a needle, via an intercostal opening in the patient, into the pericardial sac, guiding a flexible guide wire through the needle, and subsequent removal of the needle with the guide wire left in place. After removal of the needle, a tapered dilator may be advanced over the guide wire to dilate the opening in the pericardium tissue. The dilated opening, or tract, allows room for a catheter. After the dilation, the catheter is guided over the guide wire into the pericardial sac to drain fluid from the pericardium.
Thoracoscopic surgical procedures are generally less intrusive than more traditional forms of surgery, since they generally require relatively small entry openings. However, these small openings may be difficult to close, especially where the closure location is inside the patient's body. For example, referring the procedures described above, after removal of the cannula and any surgical instruments extending therethrough, the aperture formed in the tissue, e.g., the heart or pericardium tissue, is closed within the patient's body. Since these exemplary thoracoscopic procedures involve accessing the *patient's thorax through a small intercostal aperture through the patient's skin and other underlying tissues (e.g., fat and/or fascia), closure methods such as suturing are more complicated than with non-thoracoscopic surgical procedures. In particular, applying sutures with remotely operated thoracoscopic instruments is more difficult and complicated than directly manipulating a suture needle by hand at the surgical site. This difficulty can result in defective closures and/or closures that require more time than necessary.
Defective closures may expose the patient to increased risk of complications such as internal bleeding and/or infection. Even where defective closures are recognized and addressed prior to completion of the surgical procedure, the correction of defective closures increases the time required to effect the closure and may expose the tissue to additional trauma. It is generally desirable to minimize the amount of time for a surgical procedure in order to reduce the possibility of complications and unnecessary trauma to the patient.
Thus, there is a need for a closure mechanism and method that is simple to operate, reliable, and requires a small amount of time in which to form an effective closure.